In my last post I explored the manual dosing grinder, where it’s come from and how it’s commonplace today in cafes, as well as identifying some of the issues with this type of grinder. In this post I’m going to explore what I see to be the next step in grinder technology (the electronic grinder), the pros, the cons, and where we are at today.
Electronic grinders work exactly as their name suggests—you hit a button and away they grind.
They work by dosing out ground coffee through the conical burrs into a dosing chamber, which then passes into the basket over a set period of time.
So in the case of an electronic grinder, you may have it set to say 5.80 seconds to achieve the amount of ground coffee you want to have in your basket for each shot. The advantage here is that there is less chance of the barista developing an RSI (repetitive strain injury) as the amount of effort required to achieve a dose is as simple as the press of a button. Personally, I loved this when I started working behind the machine.
In addition to this, there is also a lot less wastage as the coffee directly goes into the basket itself as opposed to grinding into a dosing chamber and then waiting to be manually dosed into a basket.
Throughout the brewing process, a certain amount of coffee measured in grams into the basket is what we’re after. While the electronic grinder is accurate, the issue with its method of dosing (time-based) is that it allows for small inconsistencies in the amount of coffee in the basket, anywhere between one and three grams at a time. While only a small amount, this can create a very different extraction for a shot of espresso. Too little and the water will pass through the coffee too quickly, creating an under extraction. Too much and water can’t pass through the grounds, creating an over extraction (that burnt bitter taste I’m sure you’re familiar with).
This inconsistency of dose exists for a number of different reasons with grinder technology, but the main thing to note is that this method of calibration, time in my opinion isn't actually valid in today’s brewing methods. Just in the same way that espresso machines producing an amount (volume) of water for each programmed shot isn't actually valid either.
In my opinion, the next revolution for the specialty coffee industry will come in the form of a widely accessible grinder (or modification of existing grinders) that will produce a dose at a set amount of weight, rather than through a measurement of time.